JP5075724B2 - Occupant protection control device and occupant protection system - Google Patents

Description

 The present invention relates to an occupant protection control device and an occupant protection system.

  Generally, an SRS (Supplemental Restraint System) airbag system is known as a system for protecting an occupant in the event of a vehicle collision. This SRS airbag system is a satellite sensor such as a front crash sensor (hereinafter referred to as FCS) installed at the front portion of the vehicle or a side impact sensor (hereinafter referred to as SIS) installed on both sides of the vehicle. Detects the occurrence of a frontal collision or a side collision based on the impact data output from the vehicle, and deploys (starts up) airbags (occupant protection devices) such as driver airbags, passenger airbags, and side airbags Is.

  In this way, a control unit that detects a frontal collision or a side collision based on impact data output from satellite sensors arranged in each part of the vehicle and controls activation of the occupant protection device is called an SRS unit. It is often provided independently of an ECU (Electronic Control Unit) that performs control. Various satellite sensors have a configuration in which a sensor main body that detects an impact caused by a collision, such as an acceleration sensor, and a control circuit that performs data communication with an SRS unit are unitized. In the SRS airbag system, it is general that the satellite sensor and the SRS unit are connected to each other by a serial bus compliant with SPI (Serial Peripheral Interface) so that mutual data communication is possible. In particular, in the case of a vehicle having a long overall length including three rows of seats, a plurality of (for example, three) satellite sensors connected in a daisy chain on both sides are often arranged at predetermined intervals.

  In such an SRS airbag system, the SRS unit performs communication initialization processing (address assignment, bus switch setting, etc.) of each satellite sensor when the engine is started (when the ignition is ON). FIG. 8 is an operation flowchart regarding communication initialization processing of a conventional satellite sensor. This communication initialization process is executed for each bus line to which the satellite sensor is connected. FIG. 8 illustrates a case where a maximum of three satellite sensors are connected in a daisy chain. That is, the 1st satellite sensor in the figure represents the first satellite sensor in the daisy chain connection (the satellite sensor directly connected to the SRS unit), the 2nd satellite sensor represents the second-stage satellite sensor, and the 3rd satellite sensor. Represents the last satellite sensor.

  As shown in FIG. 8, when the engine is started, the SRS unit transmits an initialization command to the 1st satellite sensor connected to the bus line to be initialized (step S100), and a response is normally received from the 1st satellite sensor. It is determined whether it has returned (that is, initialization has succeeded normally) (step S101). If the response is not returned normally in this step S101 ("No"), the SRS unit checks the internal timer to determine whether it has timed out (step S102), and if it has not timed out ("No") ”), The initialization command is retransmitted by returning to step S100. On the other hand, if time-out occurs (“ Yes ”), the first satellite sensor is determined to be faulty and the initialization process is terminated. At this time, the SRS unit turns on a warning lamp for notifying an occupant of an abnormality of the SRS airbag system.

In step S101, if the response is returned normally from the 1st satellite sensor, that is, if initialization is successful (“Yes”), the SRS unit is connected to the bus line that is currently performing initialization processing. The presence / absence of the 2nd satellite sensor is confirmed (step S104). If the 2nd satellite sensor is present (“Yes”), the same process as the initialization process for the 1st satellite sensor described above is performed on the 2nd satellite sensor. If there is no 2nd satellite sensor (“No”), the initialization process ends normally. The same applies when the 3rd satellite sensor is present or absent.
For example, Patent Document 1 shown below is known as a technique related to a conventional communication method between a satellite sensor and a control device (SRS unit).
JP 2003-152741 A

  As described above, in the conventional SRS airbag system, when an initialization command is transmitted to one satellite sensor and a response is not returned normally, the initialization command is retransmitted until a timeout occurs, thereby determining the failure of the satellite sensor. I was going. However, for example, the operation of the satellite sensor becomes unstable due to power fluctuation and noise due to early turning of the ignition, or routing of the harness, and the initialization may not be completed before the time-out occurs. That is, although there is no abnormality in the satellite sensor itself, a response to the initialization command cannot be returned normally and there is a possibility that it is erroneously determined as a failure.

    The present invention has been made in view of the circumstances described above, and is an occupant protection control device that can prevent erroneous determination of a failure of a satellite sensor, reduce a failure occurrence rate, and improve reliability related to failure determination. And an occupant protection system.

  In order to achieve the above object, the present invention provides a first solution means for an occupant protection control device, which is connected to a satellite sensor installed at a predetermined location of a vehicle via a bus and transmits from the satellite sensor. An occupant protection control device that performs start-up control of the occupant protection device based on impact data that is generated, and includes a sensor power supply switching unit that switches supply / cutoff of power for the satellite sensor for each bus, and an initial setting of the satellite sensor As an initialization process, if an initialization command is transmitted for each bus and response data corresponding to the initialization command is not returned even after a predetermined time has passed, a satellite sensor connected to a bus that does not return the response data On the other hand, the sensor power supply switching means is controlled until the predetermined time elapses, and the response data is not returned. After the power is turned on again one or more times, characterized by comprising a control means for performing retransmission of the initialization command.

    Further, as a second solving means related to the occupant protection control device, in the first solving means, in the case where a plurality of satellite sensors are connected in series to one bus line, the control means is a leading satellite sensor. The initialization process is performed in order, and after the power is turned on again in the initialization process of any satellite sensor, the initialization command is retransmitted to the top satellite sensor and the initialization process is performed again. Features.

 Furthermore, the present invention provides a satellite sensor that is installed at a predetermined location of a vehicle and detects an impact caused by a collision, and an occupant protection for protecting the occupant of the vehicle when the collision occurs, as a solution to the occupant protection system. The occupant protection control device according to claim 1, wherein the occupant protection control device is connected to the device and the satellite sensor via a bus, and performs activation control of the occupant protection device based on impact data transmitted from the satellite sensor. It is characterized by comprising.

In the present invention, as initialization processing of the satellite sensor, an initialization command is transmitted for each bus, and if response data corresponding to the initialization command is not returned even after a predetermined time has passed, the bus without the response data being returned After the satellite sensor connected to is determined to be faulty, the sensor power supply switching means is controlled until the predetermined time elapses, and the power supply of the bus without returning response data is performed one or more times. Resend the initialization command (that is, retry the initialization process). By re-powering the bus without returning response data in this way once or multiple times, the satellite sensor may return to normal operation from an unstable operation state due to power fluctuations and noise, harness routing, etc. And the possibility that initialization is completed normally when the initialization command is retransmitted increases.
Therefore, according to the present invention, it is possible to prevent an erroneous determination on a failure of the satellite sensor, reduce the failure occurrence rate, and improve the reliability related to the failure determination.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic configuration diagram of an occupant protection system including an occupant protection control device according to the present embodiment. In the following description, an SRS airbag system employed in a vehicle having a relatively long overall length, such as a three-row seat, will be described as an occupant protection system according to this embodiment.

 As shown in FIG. 1, the occupant protection system according to the present embodiment includes a front crash sensor (hereinafter referred to as R-FCS) 10R installed on the right side of the front portion of the vehicle 100, and a front portion of the vehicle 100. A front crash sensor (hereinafter referred to as L-FCS) 10L installed on the left side, and three side impact sensors (hereinafter referred to as R-SIS) 20R1, 20R2 installed at predetermined intervals on the right side portion of the vehicle 100 20R3, three side impact sensors (hereinafter referred to as L-SIS) 20L1, 20L2, and 20L3 installed at predetermined intervals on the left side portion of the vehicle 100, and an SRS unit (occupant) installed inside the vehicle 100 Protection control device) 30, a driver airbag 50R installed on the driver's seat side, and a passenger airbag installed on the passenger seat side And grayed 50L, the right side airbag 60R which is installed on the right side portion, it is schematically composed of a left side airbag 60L which is installed on the left side portion. In FIG. 1, the driver seat airbag 50R, the passenger seat airbag 50L, the right side airbag 60R, and the left side airbag 60L are not shown.

  R-FCS10R, L-FCS10L, R-SIS20R1, 20R2, 20R3 and L-SIS20L1, 20L2, 20L3 are satellites connected to the SRS unit 30 via an SPI-compliant serial bus (hereinafter simply referred to as a bus). Each sensor is a sensor body that detects impact caused by a collision such as an acceleration sensor, and a control circuit that performs data communication with the SRS unit 30 as a unit.

  The R-FCS 10R and the L-FCS 10L detect acceleration generated by the impact of a frontal collision with an acceleration sensor, and convert an output signal of the acceleration sensor into acceleration data (impact data) as digital data by a control circuit. 30.

  The R-SISs 20R1, 20R2, and 20R3 are daisy chain connected to one bus line, each detects acceleration generated by a side collision impact from the right side by an acceleration sensor, and the output signal of the acceleration sensor is a control circuit. Is converted into acceleration data, which is digital data, and transmitted to the SRS unit 30. The acceleration data of the second stage R-SIS 20R2 is transmitted to the SRS unit 30 via the first R-SIS 20R1, and the acceleration data of the last R-SIS 20R3 is transmitted via the R-SIS 20R1 and 20R2. It is transmitted to the SRS unit 30.

  L-SIS 20L1, 20L2, and 20L3 are also daisy chain connected to one bus line, each detects acceleration generated by a side collision impact from the left side by an acceleration sensor, and the output signal of this acceleration sensor is a control circuit Is converted into acceleration data, which is digital data, and transmitted to the SRS unit 30. The acceleration data of the second L-SIS 20L2 is transmitted to the SRS unit 30 via the first L-SIS 20L1, and the acceleration data of the last L-SIS 20L3 is transmitted via the L-SIS 20L1 and 20L2. It is transmitted to the SRS unit 30.

  The SRS unit 30 receives acceleration data transmitted from the R-FCS 10R, L-FCS 10L, R-SIS 20R1, 20R2, 20R3 and L-SIS 20L1, 20L2, 20L3 via a bus, and based on these acceleration data. And detecting the occurrence of a frontal collision or a side collision, and performing deployment (startup) control of the occupant protection device, that is, the driver airbag 50R, the passenger airbag 50L, the right airbag 60R, and the left airbag 60L. Do.

  Driver airbag 50R, passenger airbag 50L, right side airbag 60R, and left side airbag 60L are provided as occupant protection devices, and are controlled by the SRS unit 30 in a frontal collision or a side collision. It is deployed at the time of occurrence to protect the occupant from the impact of a collision. These airbags are merely examples, and other occupant protection devices (for example, knee airbags, curtain airbags, seat belt pretensioners, etc.) may be provided.

  Next, a detailed configuration of the occupant protection system shown in FIG. 1 will be described with reference to FIG. As shown in FIG. 2, the SRS unit 30 includes a power circuit 31, a sensor power switching circuit (sensor power switching means) 32, an R-FCS communication I / F 33, an L-FCS communication I / F 34, and an R-SIS communication I / F. F35, L-SIS communication I / F 36, CPU (Central Processing Unit: control means) 37, memory 38, ignition circuit 39, X-axis G sensor 40 and Y-axis G sensor 41 are provided inside.

  The power supply circuit 31 is connected to an external power supply 60 such as a battery via the ignition switch 50. When the ignition switch 50 is turned on, the power supply circuit 31 is supplied with a power supply voltage (for example, 12V) from the external power supply 60. This power supply voltage is converted into an internal power supply voltage V1 suitable for the CPU 37 and the memory 38, and also converted into an internal power supply voltage V2 suitable for the ignition circuit 39. Further, the R-FCS communication I / F33, the L-FCS communication I / F34, R-SIS communication I / F35, and internal power supply voltage V3 suitable for L-SIS communication I / F36. The power supply circuit 31 supplies the internal power supply voltage V1 to the CPU 37 and the memory 38, supplies the internal power supply voltage V2 to the ignition circuit 39, and further supplies the internal power supply voltage V3 to each communication I via the sensor power supply switching circuit 32. / F33 to 36 are supplied. Since the ignition circuit 39 generates current for deploying various airbags, V2 is generally set higher than V1 and is used as a bus power source for each satellite sensor. V3 is also set higher than V1.

  The sensor power supply switching circuit 32 includes a first switch 32a, a second switch 32b, a third switch 32c, and a fourth switch 32d. The first switch 32 a switches supply / cutoff of the internal power supply voltage V <b> 3 to the R-FCS communication I / F 33 under the control of the CPU 37. The second switch 32 b switches supply / cutoff of the internal power supply voltage V <b> 3 to the L-FCS communication I / F 34 under the control of the CPU 37. The third switch 32 c switches supply / cutoff of the internal power supply voltage V <b> 3 to the R-SIS communication I / F 35 under the control of the CPU 37. The fourth switch 32d switches supply / cut-off of the internal power supply voltage V3 to the L-SIS communication I / F 36 under the control of the CPU 37.

  The R-FCS communication I / F 33 is connected to the R-FCS 10R via a bus, and transmits transmission data (for example, an initialization command) input from the CPU 37 to the R-FCS 10R, while receiving it from the R-FCS 10R. The acceleration data is output to the CPU 37. The R-FCS communication I / F 33 is operated by the internal power supply voltage V3 supplied via the first switch 32a, and the internal power supply voltage V3 is supplied to the R-FCS 10R via the power supply line included in the bus. Supply.

  The L-FCS communication I / F 34 is connected to the L-FCS 10L via a bus and transmits transmission data input from the CPU 37 to the L-FCS 10L, while outputting acceleration data received from the L-FCS 10L to the CPU 37. To do. The L-FCS communication I / F 34 is operated by the internal power supply voltage V3 supplied via the second switch 32b, and the internal power supply voltage V3 is supplied to the L-FCS 10L via the power supply line included in the bus. Supply.

  The R-SIS communication I / F 35 is connected to the R-SIS 20R1 via a bus and transmits transmission data input from the CPU 37 to the R-SIS 20R1, while outputting acceleration data received from the R-SIS 20R1 to the CPU 37. To do. The R-SIS communication I / F 35 is operated by the internal power supply voltage V3 supplied via the third switch 32c, and the internal power supply voltage V3 is supplied to the R-SIS 20R1 via the power supply line included in the bus. Supply. The bus connecting the first R-SIS 20R1 and the second R-SIS 20R2 and the bus connecting the second R-SIS 20R2 and the last R-SIS 20R3 also include power lines. When the initialization of the front-stage R-SIS is normally performed, the internal power supply voltage V3 is sequentially supplied from the front-stage R-SIS to the rear-stage R-SIS.

 The L-SIS communication I / F 36 is connected to the L-SIS 20L1 via a bus, and transmits transmission data input from the CPU 37 to the L-SIS 20L1, while outputting acceleration data received from the L-SIS 20L1 to the CPU 37. To do. The L-SIS communication I / F 36 is operated by the internal power supply voltage V3 supplied via the fourth switch 32d, and the internal power supply voltage V3 is supplied to the L-SIS 20L1 via the power supply line included in the bus. Supply. The bus connecting the first L-SIS 20L1 and the second L-SIS 20L2 and the bus connecting the second R-SIS 20L2 and the last L-SIS 20L3 also include power lines. When the initialization of the front-stage L-SIS is normally performed, the internal power supply voltage V3 is sequentially supplied from the front-stage L-SIS to the rear-stage L-SIS.

 As described above, in the present embodiment, the sensor power supply switching circuit 32 switches the supply / cutoff of the power supply for the satellite sensor (internal power supply voltage V3) for each bus to which the satellite sensor is connected. The signals transmitted to the satellite sensors via the communication I / Fs 33 to 36 include not only data such as an initialization command but also control signals such as a clock signal and a select signal. Description is omitted.

  The CPU 37 executes a control program stored in the memory 38 and controls the overall operation of the SRS unit 30. Specifically, the CPU 37 controls supply / interruption of the internal power supply voltage V3 to the communication I / Fs 33 to 36 by the sensor power supply switching circuit 32, and acceleration data input from the communication I / Fs 33 to 36. When the occurrence of a frontal collision or a side collision is detected based on the acceleration data input from the X-axis G sensor 40 and the Y-axis G sensor 41, the ignition circuit 39 is controlled to control the driver's seat airbag 50R and the passenger seat. The airbag 50L, the right side airbag 60R, and the left side airbag 60L are deployed. In addition, the CPU 37 detects each satellite sensor (R-FCS10R, L-FCS10L, R-SIS20R1, 20R2, 20R3 and L-SIS20L1, 20L2, when the ignition switch 50 is turned on). 20L3) initialization processing is executed.

  The memory 38 is a rewritable nonvolatile memory such as a flash memory or an EEPROM (Electronically Erasable and Programmable Read Only Memory), and stores a control program executed by the CPU 37 and other various data. The ignition circuit 39 is operated by the internal power supply voltage V2 for ignition supplied from the power supply circuit 31, and under the control of the CPU 37, the driver seat airbag 50R, the passenger seat airbag 50L, the right side airbag 60R, and the left side airbag. Various types of airbags are deployed by causing a current to flow through a squib for the bag 60L and igniting it. The X-axis G sensor 40 detects acceleration acting in the vehicle length direction (X-axis) and outputs acceleration data corresponding to the acceleration in the X-axis direction to the CPU 37. The Y-axis G sensor 41 detects acceleration acting in the vehicle width direction (Y-axis), and outputs acceleration data corresponding to the acceleration in the Y-axis direction to the CPU 37.

  Next, the operation of the occupant protection system according to the present embodiment configured as described above will be described. In the occupant protection system according to the present embodiment, the operations related to detection of occurrence of a frontal collision or a side collision and the control of deployment of various airbags are the same as those in the prior art, and thus description thereof will be omitted. The process will be described in detail.

  FIG. 3 is a flowchart showing communication initialization processing of each satellite sensor. This communication initialization process is executed for each bus line (for each communication I / F) to which the satellite sensor is connected. Below, the case where the communication initialization process of the satellite sensor (R-SIS20R1, 20R2, 20R3) connected to R-SIS communication I / F35 is performed is demonstrated and demonstrated.

  As shown in FIG. 3, when the engine is started (ignition switch 50 is on), CPU 37 of SRS unit 30 controls third switch 32c of sensor power supply switching circuit 32 to set internal power supply voltage V3 to R-SIS. While supplying to communication I / F35, an initialization command is transmitted to 1st satellite sensor (here R-SIS20R1) via R-SIS communication I / F35 (step S10).

  Then, the CPU 37 determines whether or not a response is normally returned from the 1st satellite sensor, that is, whether or not the initialization is successfully completed and response data corresponding to the initialization command is returned (step S11). In step S11, if the response is not returned normally (“No”), the CPU 37 checks the internal timer to determine whether it has timed out, that is, whether a predetermined time (for example, 3.5 seconds) has elapsed. (Step S12). In this step S12, when a time-out occurs, that is, when 3.5 seconds have elapsed since the initialization command was transmitted (“Yes”), the CPU 37 determines that the first satellite sensor has failed and ends the communication initialization process. (Step S13). At this time, the CPU 37 turns on a warning lamp for notifying an occupant of an abnormality in the SRS airbag system.

  On the other hand, if the time-out has not occurred ("No") in step S12, the CPU 37 controls the third switch 32c of the sensor power supply switching circuit 32 to supply the internal power supply voltage V3 to the R-SIS communication I / F 35. Once shut off (step S14), the internal power supply voltage V3 is supplied again (step S15). That is, by these steps S14 and S15, the power supply of the bus line whose response is abnormal (no response data is returned) is executed once. After the power is turned on again as described above, the CPU 37 returns to step S10 to retransmit the initialization command. In other words, if the response does not return normally, the power supply is repeatedly turned on until time-out, so the 1st satellite sensor (R-SIS20R1) is in an unstable operation state due to power fluctuation and noise, harness routing, etc. There is a high possibility of normal return, and there is a high possibility that initialization will be completed normally when the initialization command is retransmitted.

  In step S11, when the response is returned normally from the 1st satellite sensor, that is, when the initialization is successfully completed (“Yes”), the CPU 37 in the bus line currently performing the initialization process. The presence / absence of the 2nd satellite sensor is confirmed (step S16). When the initialization of the 1st satellite sensor is successful, the internal power supply voltage V3 is supplied from the 1st satellite sensor to the 2nd satellite sensor.

  In this step S16, when there is a 2nd satellite sensor (here, R-SIS 20R2) (“Yes”), the CPU 37 transmits an initialization command to the 2nd satellite sensor via the 1st satellite sensor (step S17). Then, the CPU 37 determines whether or not a response is normally returned from the 2nd satellite sensor (step S18).

  In this step S18, when the response is not normally returned (“No”), the CPU 37 checks the internal timer to determine whether or not a timeout has occurred (step S19). When the timeout has occurred (“Yes”), The 2nd satellite sensor is determined to be faulty, and the communication initialization process is terminated (step S20). At this time, the CPU 37 turns on a warning lamp for notifying an occupant of an abnormality in the SRS airbag system.

  On the other hand, if the time-out has not occurred ("No") in step S19, the CPU 37 shifts to the processing in step S14 and performs power-on of the bus with no response (no response data returned). Returning to step S10, the initialization command is retransmitted to the 1st satellite sensor. That is, if the response is not normally returned in the initialization process of the 2nd satellite sensor, the process is restarted from the initialization process of the 1st satellite sensor.

  If a response is returned normally from the 2nd satellite sensor in step S18 (“Yes”), the CPU 37 checks whether or not there is a 3rd satellite sensor in the bus line currently performing the initialization process (step S18). S21). When the initialization of the 2nd satellite sensor is successful, the internal power supply voltage V3 is supplied from the 2nd satellite sensor to the 3rd satellite sensor.

  In this step S21, when there is a 3rd satellite sensor (here, R-SIS 20R3) (“Yes”), the CPU 37 transmits an initialization command to the 3rd satellite sensor via the 1st satellite sensor and the 2nd satellite sensor (step S21). S122). Then, the CPU 37 determines whether or not a response is normally returned from the 3rd satellite sensor (step S23).

  In this step S23, when the response is not normally returned (“No”), the CPU 37 checks the internal timer to determine whether or not a time-out has occurred (step S24). When the time-out has occurred (“Yes”), The 3rd satellite sensor is determined to be out of order and the communication initialization process is terminated (step S25). At this time, the CPU 37 turns on a warning lamp for notifying an occupant of an abnormality in the SRS airbag system.

  On the other hand, if the time-out has not occurred ("No") in step S24, the CPU 37 shifts to the processing in step S14 and performs power-on of the bus with no response (no response data returned). Returning to step S10, the initialization command is retransmitted to the 1st satellite sensor. That is, if the response is not normally returned in the initialization process of the 3rd satellite sensor, the process is restarted from the initialization process of the 1st satellite sensor.

  In step S23, when a response is normally returned from the 3rd satellite sensor (“Yes”), or in step S16, it is determined that there is no 2nd satellite sensor (“No”). When it is determined in S21 that there is no 3rd satellite sensor (“No”), the CPU 37 performs communication initialization processing of the satellite sensors (R-SIS 20R1, 20R2, and 20R3) connected to the R-SIS communication I / F 35. finish.

  4 to 7 show the communication initialization process as described above in a timing chart. FIG. 4 is a timing chart when all the satellite sensors from the 1st satellite sensor to the 3rd satellite sensor are normal. As shown in FIG. 4, when all the satellite sensors are normal, the power supply to the first satellite sensor (time t1) → the transmission of the initialization command to the first satellite sensor (time t2) → to the 2nd satellite sensor Power supply (time t3) → response confirmation from 1st satellite sensor and transmission of initialization command to 2nd satellite sensor (time 4) → power supply to 3rd satellite sensor (time t5) → response confirmation from 2nd satellite sensor And the initialization process to the 3rd satellite sensor (time 6) → the communication initialization process ends normally in a series of flow of response confirmation from the 3rd satellite sensor (time t7).

  FIG. 5 is a timing chart when the 1st satellite sensor is abnormal. In this case, power supply to the 1st satellite sensor (time t1) → transmission of an initialization command to the 1st satellite sensor (time t2) → it is uncertain whether power is supplied to the 2nd satellite sensor because the 1st satellite sensor is abnormal (time t3) → Confirmation of response abnormality from 1st satellite sensor (time t4) → Control sensor power supply switching circuit 32 to turn off power (time t5) → Power on (time t6) → Send initialization command to 1st satellite sensor ( When a sequence of time t7) is repeated and a time-out is confirmed at time t8, a failure of the 1st satellite sensor is confirmed and the communication initialization process ends abnormally.

  FIG. 6 is a timing chart when the 2nd satellite sensor is abnormal. In this case, power supply to the 1st satellite sensor (time t1) → transmission of an initialization command to the 1st satellite sensor (time t2) → power supply to the 2nd satellite sensor (time t3) → response confirmation from the 1st satellite sensor and Transmission of initialization command to the 2nd satellite sensor (time 4) → It is uncertain whether power is supplied to the 3rd satellite sensor because the 2nd satellite sensor is abnormal (time t5) → Confirm response abnormality from the 2nd satellite sensor (time t6) → The sensor power supply switching circuit 32 is controlled to turn off the power (time t7) → power on (time t8) → Send the initialization command to the 1st satellite sensor (time t9), and a time-out occurs at time t10. Is confirmed, the failure of the 2nd satellite sensor is confirmed. Communication initialization process Te is abnormally terminated.

  FIG. 7 is a timing chart when the 3rd satellite sensor is abnormal. In this case, power supply to the 1st satellite sensor (time t1) → transmission of an initialization command to the 1st satellite sensor (time t2) → power supply to the 2nd satellite sensor (time t3) → response confirmation from the 1st satellite sensor and Transmission of initialization command to 2nd satellite sensor (time 4) → Power supply to 3rd satellite sensor (time t5) → Confirm response from 2nd satellite sensor and transmission of initialization command to 3rd satellite sensor (time 6) → Response abnormality confirmation from 3rd satellite sensor (time t7) → Control of sensor power supply switching circuit 32 to power off (time t8) → power ON (time t9) → Send initialization command to 1st satellite sensor (time t10) A series of flows are repeated, and at time t11 When out is confirmed, the communication initialization process failure is determined in the 3rd satellite sensor is abnormal termination.

  As described above, according to the passenger protection system including the SRS unit 30 according to the present embodiment, the power supply of the bus whose response to the initialization command is abnormal (the response data corresponding to the initialization command is not returned) is re-established. When the power is turned on, the satellite sensor is more likely to return to normal operation from an unstable operation caused by power fluctuations and noise, or harness routing, and initialization is completed normally when the initialization command is retransmitted. The possibility increases. As a result, it is possible to prevent an erroneous determination on the failure of the satellite sensor, reduce the failure occurrence rate, and improve the reliability related to the failure determination.

  In the above embodiment, the number of power-on operations performed at one time is set to one (steps S14 and S15). However, after this power-on is performed a plurality of times, the initialization command is retransmitted to the first satellite sensor. You may make it do. This further increases the possibility that the satellite sensor returns to normal from the unstable operation state. In the above embodiment, the communication initialization processing of the satellite sensors (R-SIS 20R1, 20R2, and 20R3) connected to the R-SIS communication I / F 35 is exemplified, but the other satellite sensors also perform similar communication initialization. Initialization can be performed by processing.

  Moreover, although the said embodiment demonstrated the case where the power supply line was included in the bus | bath which connects a satellite sensor and communication I / F, this power supply line is a bus | bath including a data line, a control line, etc. When separated and provided separately, the sensor power supply switching circuit 32 and the power supply line may be directly connected without using the communication I / F. Further, in the case where the power supply voltage is supplied to the power supply line separately provided in this way by the power supply circuit provided outside the SRS unit 30, the sensor power supply switching circuit 32 is provided outside the SRS unit 30. It is good also as a structure.

It is a composition schematic diagram of a crew member protection system provided with a crew member protection control device (SRS unit 30) concerning one embodiment of the present invention. It is a detailed explanatory view of an occupant protection system according to an embodiment of the present invention. It is a flowchart showing operation | movement of the passenger | crew protection system which concerns on one Embodiment of this invention. It is a 1st timing chart showing operation | movement of the passenger | crew protection system which concerns on one Embodiment of this invention. It is a 2nd timing chart showing operation | movement of the passenger | crew protection system which concerns on one Embodiment of this invention. It is a 3rd timing chart showing operation | movement of the passenger | crew protection system which concerns on one Embodiment of this invention. It is a 4th timing chart showing operation | movement of the passenger | crew protection system which concerns on one Embodiment of this invention. It is a flowchart showing operation | movement of the conventional passenger | crew protection system.

Explanation of symbols

 100 ... Vehicle, 10R, 10L ... Front crash sensor, 20R1, 20R2, 20R3, 20L1, 20L2, 20L3 ... Side impact sensor, 30 ... SRS unit, 50R ... Driver's seat airbag, 50L ... Passenger seat airbag, 60R ... Right Side airbag, 60L ... Left side airbag, 31 ... Power supply circuit, 32 ... Sensor power supply switching circuit 32, 33 ... R-FCS communication I / F, 34 ... L-FCS communication I / F, 35 ... R-SIS communication I / F, 36 ... L-SIS communication I / F, 37 ... CPU, 38 ... Memory, 39 ... Ignition circuit, 40 ... X-axis G sensor, 41 ... Y-axis G sensor, 50 ... Ignition switch, 60 ... External power supply

Claims (2)

An occupant protection control device that is connected to a satellite sensor installed at a predetermined location of a vehicle via a bus and performs start-up control of the occupant protection device based on impact data transmitted from the satellite sensor,
A plurality of satellite sensors are connected in a daisy chain for each bus line, and provided independently for each bus line, the sensor power supply switching means for switching supply / cutoff of power for the satellite sensors; ,
As an initialization process of the plurality of satellite sensors connected to each bus line in a daisy chain , an initialization command is transmitted in order from the first satellite sensor of each bus line, and the initialization command is transmitted even after a predetermined time has elapsed. If the response data corresponding to is not returned, it is determined that one of the satellite sensors connected to the bus line to which the response data is not returned is a failure, and the response data is not returned until the predetermined time has elapsed. A bus line which does not return the response data after controlling the sensor power supply switching means corresponding to the bus line and performing power supply reactivation one or more times corresponding to only the bus line which does not return the response data Control means for retransmitting the initialization command to the satellite sensor at the top of the
An occupant protection control device comprising: A satellite sensor that is installed at a predetermined location of the vehicle and detects an impact caused by a collision;
An occupant protection device for protecting an occupant of the vehicle when the collision occurs;
The occupant protection control device according to claim 1, wherein the occupant protection control device is connected to the satellite sensor via a bus and performs start-up control of the occupant protection device based on impact data transmitted from the satellite sensor.
An occupant protection system comprising:

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